1. Ferdinand must step out to pick up Messi

Barcelona's principal threat is obvious, the mesmeric Lionel Messi and the combination play he strikes up with Xavi Hernández and Andrés Iniesta in particular, bursting through the centre and bypassing defenders with clever passing exchanges. Manchester United will be aware of that and must seek to close the space between their own back-line and midfield ranks to make sure Messi has less room to work in. Occasionally, Rio Ferdinand will have to be brave and step out to pick up the Argentinean. By doing that, they will clearly risk leaving open space in behind, but Barça aren't a team who seek to play David Villa in with balls over the top. Even so, Edwin van der Sar will have to be alert and sweep up any passes lofted over his defenders. The Premier League side must keep their shape and, when Messi drifts to the flanks, Patrice Evra and Fábio da Silva must be aware. To take a man out and man-mark the brilliant Argentinian would be counter-productive.

2. Encourage Park to attack marauding Alves

United must be proactive in terms of their selection and approach. In Rome back in 2009, Wayne Rooney was asked to play wide left with little effect. This time around, Park Ji-sung's energy must be employed in that position with the South Korean charged with attacking Dani Alves, a player happiest when marauding down the flank as a supplementary attacker, and try to make the full-back concentrate on defending. He is uncomfortable when pushed back into his shell. United must seek to pin back the Brazilian and, when the free-flowing full-back does break free to join his midfielders in their forward forays, the Premier League team must seek to exploit the space he has left behind on the counterattack once possession is prised from the Catalans.

3. Rooney must hassle Busquets in possession

Rooney, in a central role, will carry an attacking threat for United but he has defensive duties to play as well. The England forward must sit on Sergio Busquets, Barcelona's deepest-lying midfielder, when the Catalans start passing the ball out from the back. Busquets is their go-through man, a distributor with a fine passing range but the man who presents the play to the creative talents ahead. Yet, as Real Madrid showed in the semi-finals, the Spain international can become irritated if he is afforded close attention. Rooney must cramp his style, hassle and buzz around him, making sure Busquets is continually harassed when in possession. He can help cut off Barça at their source.

4. Close down Valdés and make him kick long

Víctor Valdés likes to start attacks, distributing to Busquets or his centre-halves when he collects the ball in open play, and, if only intermittently, United must close down the goalkeeper and those around him to force him to kick long. They have to snap on to the goalkeeper and push in on his centre-backs, who tend to split, and the deep-lying midfielder. They have to cut out the angle for Valdés and leave him no options. That will play into United's hands – their strength will be in the aerial ability of Nemanja Vidic and Ferdinand, who are so happy dealing with that kind of delivery. It will not be something they can do every time Valdés collects, because it will expend energy, but now and again they must push on tight and force him out of his comfort zone.

5. Stay disciplined and keep 11 men on the pitch

United, above all, must remain disciplined. Barcelona's tie with Real Madrid in the semis was always likely to be fractious given the antagonism between the two bitter rivals, but what those games proved is that, when the Catalans are not smooth and comfortable in their possession, they can quickly become irritated and lose their focus. In contrast, it is vital that United stay cool and do not risk a sending off, which would make their task even more daunting. Barça cherish the ball and love being in possession; United have to retain a full complement to confront them effectively.

I think our defensive duties are important, but more than that I think Man Utd need to come out and attack. One thing Barcelona can't stand is other attacking teams, and specially those that are good at it. If you think back to the last clasicos, the best one for RM was the one they attacked. Barcelona is very used to any kind of pressure, so playing defensive is simply not going to cut it. We need to use our fluidity and attack.

That's a nice analysis, but I don't think everything on there would work. Here is my analysis of each of them:

1. Earlier on in the season, I can remember a few Villa goals with balls from over, so the tactic depends on Villa's form. Granted that it's been poor of late, but he relishes big occasions, United will have to pray he remains invisible on the field. A much safer tactic: rely on Fletcher to do what Busquets does to star attacking midfielders/CFs of other teams. For United, Fletcher will be the key, he has to frustrate Messi. This will take a lot of pressure of the defense.

2. This is a good idea if Park can be spared for such a purpose when Barcelona have the ball. I think it makes sense for United to defend from the front, so everyone except Chicharito will have to be on defensive duty.

3. At first it seems like a good idea. But I am sure SAF has considered the possibility that this will prompt Pique to take his place in tiki-taka duties in the lower midfield, with Busquets falling back trying to take Rooney with him. Nevertheless, a useful plan that could surprise us in the first few minutes and break the tempo.

4. Again seems like a decent idea, but this will be hard to keep up. Remember also that the most aggressive players in the Barcelona side are our goalkeepers. Valdes can be hassled but the mistakes this might induce will be at best minor.

5. Crucial. If United can't do this then they have lost the game even before it's started. However everything I have heard (Ferdinand, SAF, O'Shea, Van Der Sar) suggests that United will be patient and not throw the game away in frustration.

A final comment is that Guardiola's big game plan is virtually identical to his regular plan with one difference: in big games, the midfielders aim to be found in unexpected places, because they know that MVP have been taken care of by the other team's tactics. Think Xavi against Madrid in the 5-0 Clasico. It is dangerous to mark players for this reason (both the 5-0 and United's loss in 2009 can basically be attributed to shock early goals). I have no doubt this will be a feature of our attacking play in the first fifteen minutes of the game.

Agree about the marking thing. It's very hard to effectively man mark Barcelona's players, they are fairly fluid in position. Man marking would probably work against a team like Inter or Bayern, but to confront Barcelona like that would be very difficult.

I want to see Vidic tackle Busquets really hard to make him fall over without him having to dive.

imo fletcher is overrated...all he does is run around and chase the ball which barca can definitely deal with...the difference with pepe was that he was also physically powerful and imposing as well as extremely athletic which helped him stifle messi for most of the 3 clasicos he played in this spring. besides man united have park, who can also actually pass and create things offensively, to do that job. SAF should go with valencia, carrick, park, giggs in midfield with rooney dropping even deeper than usual to help out